Apparatus for processing thermoplastic yarns



April 4, 1961 N. E. KLEIN ET AL 2,977,746 APPARATUS FOR PROCESSING THERMOPLASTIC YARNS Filed June 9. 1958 5 Sheets-Sheet 1 FIG. '2" F/G'.'/'

INVENTOR. NORMAN E. KLEIN CYRIL e. EVANS BY ATTORNEY April 4, 1961 N. E. KLEIN ETAL APPARATUS FOR PROCESSING THERMOPLASTIC YARNS Filed June 9, 1958 5 Sheets-Sheet 3 INVENTOR. NORMAN E. KLEIN OYRIL G. EVANS BY f3! ATTORNEY APPARATUS FOR PROCESSING THERMOPLASTIC YARNS Filed June 9, 1958 April 4, 1961 N. E. KLEIN ET AL 5 Sheets-Sheet 4 3 O8 468 B0 2 20 M 5 3 5 662 98 2 2222 22 2 222 22 J I I} I If I- I 7 7 J, 6 0X0 .1 i R= R24 2 1 W \L 3 M A 1 W 2 I 1 mm O o 62 4 m2 2 40 2 j 4. 2 1 M02 M6 4 22 23 2 4 3 2 2 6 3 9 3 I 8 2 a T 4 .l 2 0 2 9 9 NORMAN E. KLEIN CYRIL G. EVANS BY April 4, 1961 N. E. KLEIN ETAL 2,977,746

APPARATUS FOR PROCESSING THERMOPLASTIC YARNS Filed June 9, 1958 5 Sheets-Sheet 5 NORMAN E. KLEIN CYRlL G. EVANS ATTORNEY United States Patent F APPARATUS FOR PRQSQZSSING THERMOPLASTIC RNS Norman E. Klein, Pendleton, and Cyril G. Evans, Clemson, S.C., assignors to Deer-ing Milliken Research Corporation, Pendieton, S.C., a corporation ofDelaware Filed June 9, 1958, Ser. N... 740,637

24 Claims. c1. 57-34 This invention relates to apparatus for .processin g'yarns and more particularly the invention relates to thermally treating thremoplastic yarns and to novel apparatus whichv employed in the manufacture of such articles. In most.

instances the primary reason for employing an elasticized yarn in the manufacture of such fabrics and articles is to" obtain a fabric having a resilient or elastic nature, but in some instances the primary reason for emplying an elasticized yarn is to obtain a fabric of increased bulk, and in still other instances both of these characteristics are equally desired. Products having one or both of these characteristics as a result of being fabricatedfrom elasticized yarns have been widely acceptedaand are presently sold in large volumes.

An elastic nature can be imparted to a thermoplastic" yarn by any of several well-known processes. A first such process comprises highly twisting a yarn, heat-setting the twist therein and thereafter untwisting the yarn 1 so that the filaments thereof are highly stressed. Such a process can be accomplished with conventional yarn twisting and heat-setting apparatus or it can be accom plished with false-twisting apparatus especially designed for the purpose, but in this specification no distinction is made between yarns produced with the different types of twisting apparatus, and all such yarns are referred to' as torque elasticized yarns.

A second procedure for imparting an elastic nature to an end of yarn comprises passing it, while at an elevated temperature, about the sharpened edge of a blade member to thereby stress the yarn such that the filaments thereof tend to assume a highly convoluted configuration. This method of elasticizing continuous filament, thermoplastic yarns is highly desirable for the reason that yarns elasticized by this method normally have little or no tendency to twist and can readily be employed single ply. It also differs from most other methods of elasticizing thermoplastic yarns in that the elastic nature of a yarn processed in this manner is only partially apparent following passage of the yarn about the blade edge, and .a heat teratment is necessary to develop its full elastic nature.

Yarns elasticized by this procedure are referred to in this specification as edge elasticized yarns.

Still other methods for imparting an elastic nature to continuous filament, thermoplastic yarns comprise the steps of mechanically crimping the yarn and heat-setting the resulting crimp therein. The mechanical crimping" necessary in such processes can be accomplishedbylany; one of several different procedures'such'aspassing the yarn through a pair of matching corrugated rolls, forc 'lce e ing the yarn into a crimping chamber or by knitting the yarn into a closely knit fabric from which-it is sub- ?atented Apr. 4, 196,1

sequently unraveled, and yarns produced by all such methods are referred to in this specification as mechanically crimped yarns.

It has recently been found that the characteristics off elasticized yarns, such as above described, can be modified by an overfeed thermal treatment to make the yarns especially advantageous for certain applications, and increasing quantities of elasticized. yarns are being thus treated. The apparatus employed for post-treating elastici'zed yarns in this manner comprises, in more instances, a yarn supply means, a first yarn advancing means, a plate-type heater, a second yarn advancing: means which advances the yarn at a slower rate than thefl V first yarn advancing means, and a yarn collecting means. A

This apparatus is completely separate from the yarn elaticizing apparatus, and the fact that separate apparatus is required for the elasticizing and post-treating operations necessitates a relatively high expenditure for equipment and floor space.

In addition, processing costs are relatively high because of the labor required to handle the yarn a plurality of times and the power required to heat the two separate yarn heaters used in the elasticizing and post-treating apparatus.

It is an object of this invention to provide improved apparatus for post-treating elasticized yarns.

It is another object of this invention to provide apparatus, utilizing a single heater, which can be employed for simultaneously edge elasticing and post-treating a thermoplastic yarn or which can be employed for performingeither of these operations independently.

It is another object of the invention to provide apparatus which can be employed for elasticizing and post-treating a plurality of yarns, and for thereafter twisting the yarns together to form a plied yarn of relatively high total denier.

It is still another object of the invention to provide" improved apparatus for performing one or more processing operations, at least one of which utilizes elevated' temperatures, upon one or a plurality of ends of thermoplastic yarn.

It is a further object of the invention to provide edge-g; elasticizing apparatus which simplifies the variation and control of process variables.

According to this invention there is provided :apparatus' comprising a rotary heater, a yarn advancing means to' advance one or a plurality of ends of thermoplastic yarn I to said rotary heater at a first selected linear rate, a seci ond yarn advancing means to withdraw said one or more ends of yarn from the yarn heater at a second linear, rate, and means to rotate said yarn heater such that it: has a selected surface speed relative to the rate at which said one or more ends of yarn are advanced by the yarn.

advancing means.

Preferably the yarn heater comprises,

a stepped roll having two different heating surfaces of different diameters and the apparatus preferably com prises still another yarn advancing means to advance one "1 or more ends of thermoplastic yarn to the larger diameter portion of the stepped roll heater, and a blade. means with an edge operatively positioned closely adja-' cent the larger diameter portion of said heater suchthat said one or more ends of yarn can be withdrawn from the larger diameter portion of said yarn heater and about the edge of the said blade member in an acutely angular path. With this construction, the smaller diameter portion of the yarn heater can be employed fora post-treatment operation and a single yarn advancing. means can be employed to withdraw the yarn or yarns;

from the larger portion of the heater" and ,feed thfe" same to thesmaller diameter portion of'the heater.

The apparatus is also preferably provided with driving means of novel type to be subsequently described which enables one to readily vary the relative rate of advance of the yarn by the several yarn advancing means.

A post-treating operation, such as above described, is performed in instances when it is desired to impart to a yarn an exceedingly bulky nature, and apparently results in this characteristic being imparted to a yarn by providing conditions which are favorable to the crimps in adjacent filaments of the yarn being formed out of phase, the word crimps being here employed to include undulations, coils, and kinks. In other words, at the point where the yarn comes into contact with the yarn heater in a process of this type, there is no lateral restraint on the yarn, and the restraint to the forward motion of the yarn offered by the yarn heater promotes lateral expansion of the yarn at a point in the yarn path immediately preceding the yarn heater. Lateral expansion of the yarn results in the filaments thereof being spatially separated so that the crimps in each filament can form independently and such that the crimps in adjacent filaments are largely out of phase or at least do not precisely coincide. It will readily be seen that a yarn can have a high measure of elasticity with very little bulk if the crimps in adjacent fibers are largely in phase but that if the crimps are out of phase, this results in adjacent yarn fibers being normally held apart from each other except for periodic spaced points of contact.

In addition to providing conditions such that the crimps in adjacent yarn fibers tend to initially form out of phase, the overfeed thermal treatment also serves to at least partially heat-set the crimps in this condition to thereby reduce the tendency for the crimps, after they have been removed by tensioning the yarn, to reform such that they are largely in phase. Further, the overfeed thermal treatment acts to at least partially stabilize the yarn so that its degree of elasticity is not subsequently subject to such large changes as a result of the release of latent stresses and, in the case of edge elasticized yarns, also serves to develop a portion of the crimp which was originally latent in nature.

The use of a rotary heater for performing an overfeed thermal treatment on an elasticized yarn has found to be surprisingly advantageous, and this is particularly so in the case of edge elasticized yarns. Heretofore, it has been a general practice to employ a stationary plate heater for post-treating elasticized yarns and such posttreated yarns have been generally satisfactory, but it has now been found that the tension necessary to slide an elasticized yarn over the surface of a yarn heater, at least in some instances, adversely affects the properties of the yarn and that one can obtain a yarn having a higher degree of stabilized crimp and appreciably greater bulk, other factors being equal, with a rotary heater than with a plate heater. Further, the rate of heat transfer to the yarn with a rotary heater is excellent so that heat-setting of the yarn can be accomplished in a very short period of time and relatively high yarn velocities can be maintained without sacrificing quality in the finished product.

A preferred specific embodiment of apparatus according to this invention will now be described with reference to the accompanying drawings in which:

Figure l is a schematic view in perspective showing principal parts in location.

Figure 2 is a front elevational view of the crimping and/lor heat-treating component of the apparatus of Figure Figure 3 is a side elevation view of the crimping and/ or heat-treating component of the apparatus as it would appear looking from right to left in Figure 2.

Figure 4 is a side elevation view of the crimping and/or heat-treating component of the apparatus as viewed from the left in Figure 2 of the drawings.

Figure 5 is a sectional view of the crimping and/or I heat-treatihg portion of the apparatus taken usages;

5--5 of Figure 4. f; Figure 6 is a rear elevational view of the crimping and/or heat-treating component of the apparatus.

Figure 7 is an enlarged cross-sectional view of the heater roll assembly taken substantially along line 7-7 in Figure 4.

Figure 8 is a cross-sectional view of the unheated guide roll assembly taken substantially along line 88 of Figure 4.

Figure 9 is a bottom view of one end of the blade holder arm.

With reference to Figure l of the drawings in greater detail, there is illustrated a frame member 10 which can be and preferably is a portion of a conventional downtwister frame, and supported by member 10 is a plurality of yarn supply means two of which are illustrated and generally indicated by the reference numerals 12 and 14. Yarn supply means 12 and 14 comprise respectively spindles 16 and 17 for centrally supporting pirns or the like of yarn 18 and 19 so that ends of yarn 20 and 22 can be withdrawn from the pirns in an over-end manner through guide means 24 and 26, positioned on the extended central axes of spindles 16 and 17. As will subsequently be more apparent, the apparatus of this invention can be employed to simultaneously process four or more ends of yarn by the provision of a corresponding number of yarn supply means, but for a full understanding of the invention only two supply means need be illustrated.

From guide means 24 and 26 the yarn ends 20 and 22 are passed to tension regulators 28 and 30 which can be and preferably are of the design disclosed in 11.8. Patent 2,790,611. The ends 20 and 22 are then passed to a combination edge crimping and heat-treating assembly which is generally indicated by reference numeral 32, and which will subsequently be described in greater detail. After being elasticized and/or post-treated, the yarn ends 20 and 22 are guided about an oil roll 34 which dips into a supply of oil within a trough 36 and is rotated by an electrical motor 38 at a rate calculated to supply an amount of oil to the yarn ends 20 and to place them in a proper condition for weaving, knitting, or the like. The yarn ends 20 and 22 are then passed through a guide 40 to a twisting and take-up means generally indicated by the reference numeral 42 and here illustrated as comprising a conventional ring and traveler array. The means 42 twists the ends of yarn 2t) and 22 to form a plied yarn which is then collected on a suitable core or the like indicated by the reference numeral 44.

The apparatus also includes driving means (not illustrated) for the take-up means 42 and means to selectively engage and disengage the driving means so that operation of the take-up means can be temporarily discontinued in case of a yarn break or to replace the cone 44 when it has collected a full supply of yarn. These two components of the apparatus can suitably be of conventional design and construction, however, and for this reason will not be described in detail.

With particular reference to Figuers 2 to 9 of the drawings, there is illustrated two support members 46 and 48 to which there is secured by means of bolts 49 and 50 a support housing 52 and secured to the upper edge of housing 52 by means of screws 54 and 56 is an arm 58 having on its upper extremity an integrally formed bracket member 60 for supporting yarn tensioners 28 and 30. Also supported by arm member 58 is a first guide means 62 preferably formed of a ceramic material and having a plurality of guide channels 64 for maintaining the ends of yarn 20 and 22 in spaced relationship. Positioned immediately below guide member 62 and also supported by arm 58 is a comb type guide means 66 having a plurality of pin members 68. The guide member 66 is adjustable pivotally in a generally vertical plane by virtue of being secured by a single screw 69 which Lil 'can'be loosened for adjustment of the, guide means '66.

Journaled. through a :bushing member .70 and freely rotatable as aresult of being mounted in antifriction bearings 71 and 72, is a shaft 73 which carries one roll 74 of a first yarn advancing means generally indicated bythe reference numeral 76. Bushing :7 extends through a slot 77 in one side wall of support housing 52 and is .secured in position by a nut 78 which threadably engages the external end .of the bushing. The nut 78 also serves to secure one end of an elongated support plate 79 having an opening through which bushing 70 extendsand this construction has the advantage that it permits plate 79 to be pivoted, for position adjustment purposes, about the centr l xi f shaft. 73 by leo ening nu 78.. Th Plate 79 carries as b shaft 80 extending at a small angle to the axis of shaft 73 and about which is journaled a second roll .82 of yarn advancing means 76.

a n d ancing means 76 is a d uble yarn advancing means designed to positively advance a plurality of strands of yarn on two different occasions at two different linear rates and for this reason each of rolls 74 and 82 are provided with corresponding portions of different diameters. Roll 74 has a first portion 84 of larger diameter which is; separated by a flange 86 from a second portion 88 of smaller diameter, and roll-82 has corresponding portions 90 and 92, separated by a flange 94. Rolls 74 and 82 are provided with peripheral grooves 96 and 98 respectively, and a drive belt 100 rests within grooves 96 and 98 and extends about rolls 74 and 82 to insure that the two rolls are rotated such that corresponding portions thereof have the same surface speeds. The yarn ends and 22 pass through tension regulators 28 and 30, aboutguide means 62 and 66 and wrap one or more turns about rolls 74 and 82, so that they are positively advanced along the yarn path at a selected linear rate dependent upon the rate of rotation of the rolls 74 and 82. As a result of the axis of rotation of roll 74 being at an angle to the axis of rotation of roll 82, adjacent wraps of yarn about the two'rolls remain in spaced relationship and there is little or'no abrasion .of the yarn.

From the yarn advancing means 76, the yarn ends 20 and 22 are passed in spaced relationship through a comb type guide means 102 secured to a laterally extending appendage 104 of arm 58 by any suitable means such as screw I06, and are thereafter passed to a yarn heater generally indicated by the reference numeral 108. The heater 108 comprises a stepped roll 110 carried by a shaft 112 (see Figure 7) journaled through antifriction bearings 114 and 116 mounted within a support sleeve member 118 which extends partially through the roll 110 and which is threaded into a suitable opening 120 in the wall of support housing 52. Means comprising an oil tube 121 and cup 122 are provided for introducing a lubricant to the surface of shaft 112 intermediate bearings 114 and 116. Carried by one end of shaft 112 is a hub member 124 from which extend a plurality of legs, one of which is visable at 126, for supporting an annular heat distributing member 128 L-shaped in cross section. The number of legs carried by hub 124 should be the minimum necessary for adequate support of member 128 and three legs are generally sufficient. Also, the legs 126 and the sleeve member 118 are preferably formed of a material such as stainless steel having a relatively low coeflicient of thermal conductivity (i.e. below 0.1 or 0.2 calories per second per degree centigrade at 100 C.) so that the heat loss by conduction and the temperature of bearing members 114 and 116 are held to a minimum.

Heat distributing member 128 serves as a support for a first annular yarn contact member 130 and a second annular contact member 132 of smaller diameter provided, in each instance, with yarn guide grooves 134 and 136 respectively, which serve to maintain a plurality of ends of yarn, while in contact with the peripheral surf ces of, m r 130. 24 1 i spa ed re aticnsh p with respect to each other. Yarn contact members 130 and 132 are subject to considerablefwear as a result of being continually in contact, when the apparatus is in operation, with one or more running lengths of yarn and for this reason they are preferably made of a wear resistant material such as stainless steel- Since, however, such materials generally donot have a high thermal conductivity, members 130 and 132 should be relatively thin in radial thickness and should be in Contact with heat distributing member 128 over as large an area as possible. The member 128 is preferably formed from a material such as copper having a relatively high coefficient iOf thermal conductivity (i.e., above 0.2 or 0.3 calories per degree per second at C.) to insure even and rapid heat transfer to the inside surfaces .of yarn contact members and 132.

The annular heat distributing member 128 is heated by an electrical resistance heater 138 which is secured to one side face of the member 128 by any suitable means and extends substantially the entire distance around they side face of member 128. The electrical resistance heater 138 is supplied with an electric current by means of conductor 140 which extends from one end of heater 138, axially of shaft 112, to a 'slip ring 142 insulated from shaft 112. Theother end of heater 138 is grounded to heat distributing member 128 which is supported by legs 126, hub 124 and shaft 112, all pro viding in sequence an electrical return circuit to a second slip ring 144 which is threaded onto a smaller section of shaft 112. A carbon brush 145 is mounted in a suitable holder 146 and is in sliding contact with slip ring 142, and a second carbon brush 148, mounted in a holder 149, is'in electrical contact with slip ring 144. Tocomplete the electrical circuit, brushes 145 and 148 are connected to a suitable source of electrical power preferably through a variable transformer, rheostat or the like, so that the energy supplied to heater 138 can readily be controlled to maintain the yarn contact members 130 and 132 at a proper temperature.

To further reduce the heat loss from the heated surfaces of heater 103, a disc of insulating material 150 is disposed between the member 128 and the adjacent face of housing 52 and a second disc or ring 152 of insulating material is disposed on the other side of member 128 and includes portions 154 which extend between the leg members 126. The discs of insulating material 150 and 152 are held in position by end plates 156 and 157 and by a plurality of bolts 158 which extend through the -two dics of insulating material and clamp the same against opposite side faces of annular member 128.

After passing in a partial wrap about yarniheater 108 Within grooves 134 of member 130, the yarn ends 20 and 22 are withdrawn in a sharply angular manner about the sharpened edge 159 of a blade member 160 such that the edge 159 is positioned at the apex of the acute angle in the yarn path. The blade edge 159 is operatively positioned in such close proximity to yarn contact member 130 of heater 108 that the yarn ends 20 and 22'have little opportunity to cool before their contact with the blade edge and are at an elevated temperature as they pass about the blade edge. The blade member 160 is held in position by a blade holder means, generally indicated by the reference numeral 162, which will subsequently be described in detail.

To assist in guiding the yarn ends 20 and 22 about the edge of blade member 160 and to aid in controlling the tension in the yarn ends 20 and 22 as they pass about edge 159, there is provided an unheated roll indicated by the reference numeral 164. The roll 164 can be suitably formed from stainless steel or any other wear'resistant material and preferably has a smooth peripheral surface against which the yarn ends 20 and 22 can be passed in sliding frictional contact. Roll 164 is carried by a shaft 166 which is journaled through a bushing 168 and is freely rotatable by. virtue of antifriction bearings friction bearings 194 and 196. through a slot 200 in housing 52 and is secured in posiand serve a plurality of positions of apparatus.

'7 170 and 172. Bushing 168 is mounted within a slot 174 m the side face of housing 52 and isretained in position by a nut 176 which threadablyengages the externally extending end of the bushing.

From roll 164 the yarn ends 20 and 22 are passed to a guide means 178 here illustrated as being of the helical type. Helical guide 178 serves to retain theyarn ends 20 and 22 in spaced relationship with respect to each other and is carried by an arm member 180 which is secured to housing 52 by a screw 182. From guide 178 the yarn ends 20 and 22 are again passed to yarn advancing means 76, are wrapped one or several turns about the smaller diameter portions 88 and 92 of rolls 74 and 82 and are thereafter passed to a comb type guide 184 which again serves to retain the yarn ends 20 and 22 in spaced relationship with respect to each other. From guide 184 the yarn ends 20 and 22 pass in a partial wrap about the heated annular member 132 of yarn heater 108 and thereafter about a pin guide member 186 carried by arm 180. The yarn ends 20 and 22 are then passed to a second yarn advancing means generally indicated by the reference numeral 188.

The yarn advancing means 188 is generally similar to yarn advancing means 76 and comprises a first roll 190 carried by a shaft 192 which is journaled through a bushing 193 and which is freely rotatable by virtue of anti- Bushing 193 extends tion by a nut 202. A support plate 204 is secured between housing 52 and nut 202 so that it is adjustably pivotable about the axis of roll 190, and carried by plate a 204 is a stub shaft 206 about which a second roll 208 -is journaled. Rolls 190 and 208 are in each instance also be noticed that the axis of rotation of rolls 190 and 208 are at an angle to each other so that a plurality of turns of yarn wrapped about the two rolls remain spatially separated from each other. From yarn advancing means 188, yarn ends 20 and 22 are passed to the oil roll 34 and take-up means 42 in the manner previously described.

Extending through the lower bottom portion of housing 52 is a drive shaft 212 which is driven in synchronism with the drive means for take-up means 42 and which can conveniently extend the length of a twister frame Shaft 212 carries a drive gear 214 within housing 52 which meshes with a driven gear 216 The latter being journaled about a sleeve member 218 threaded through a suitable orifice in the wall of support housing 52. Gear 216 is freely rotatable by virtue of bearing 220 and has secured to one of its side faces a first disc shaped clutch member 222 of a clutch generally indicated by the reference number 223. Clutch member 222 is designed to engage a second clutch member 224 carried by one face of a multiple gear 226 journaled for rotation on antifriction bearings such as ball bearings 228 positioned on a stub shaft 230 which extends through sleeve 218. The interior surface of sleeve member 218 and the surface of stub shaft are provided with matching threads so that by rotation of stub shaft 230, it is moved axially to eifect engagement or disengagement of clutch 223. A pinion 232 is secured to one end of stub shaft 230 by means of a set screw 234 and meshing with pinion 232 is a gear rack 236 on one end of a control rod member 238 which is movable lengthwise by virtue of a roller 240 secured to housing 52 by means of a screw 242 and a second guide 244 which is secured to housing 52 by suitable means such as screws 246 and 248. The control rod has a handle portion: 250 which extends to the front of the apparatus to permit an operator to readily effect lengthwise movement 'of the control rod member 238 so that pinion 232 is rotated andclutch members 222 and 224 are brought togetheror separated as desired.

252 and are secured to gear member 254 by screws 264,

265, and 266. This construction permits one to readily exchange gear members 258 and 260 for gears of different sizes and as will subsequently become apparent. This is an advantageous feature of the apparatus.

Gear member 254 drives heater roll 110 through a gear 268 secured to shaft 112 by means of a set screw 272 and also drives the unheated roll 164 through a gear 274 secured by means of a nut 275 to a flanged bushing 276 which in turn is secured to shaft 166 by means of a set screw 278 (see Figure 8). This construction is advantageous for the reason that it permits one to readily exchange gear 274 for other gears of different sizes to thereby vary the rate of operation of unheated roll 164 with respect to the rate of operation'of heater roll 110. To make possible proper meshing of gears 254 and 274 with variation in the size of gear 274, a jack screw 282 is threaded through support housing 52 and abuts against bushing 168. Since jack screw 282 is approximately aligned with the slot 174 through which bushing 168 is mounted, one can be loosening nut 176 and adjusting jack screw 282 precisely position shaft 166 at varying distances from the periphery of gear 254 to accommodate gears of different sizes.

The two readily exchangeable gears on multiple gear 226 serve to drive yarn advancing means 76 and 188. Gear 260 drives yarn advancing means 76 through a small gear 284 which is secured to shaft 73 by any suitable means such as set screw 286, and gear 258 drives yarn advancing means 188 through a small gear 288 secured to shaft 192 by means such as set screw 290. The distance of shaft 73 from gear 260 is precisely adjustable by virtue of the slot 77 in housing 52, nut 78, and a jack screw 292 threaded through housing 52 in general alignment with the longitudinal axis of slot 77, and this permits adjustment to secure proper meshing of gear 260 and gear 284 with a relatively large variation in the relative sizes of the two gears. Similarly, the distance of shaft 192 from the periphery of gear 258 is readily adjustable by virtue of slot 200, nut 202, and a jack screw 294 so that the relative size of gear 288 with respect to gear 258 can also be readily varied.

The above constructionis exceedingly advantageous since it permits the rate of operation of both yarn advancing means 76 and yarn advancing means 188 to be varied in a systematic manner wth respect to the rate of rotation of heater roll 110. For example, if gear 254 is constructed with an even teeth and gear 260 has the same size teeth as gear 254, a change of one tooth in gear 254 represents a change of exactly 1% in the rate of operation of yarn advancing means 76 with respect to the rate of rotation of heater roll and the relative rate of operation of these two components can be varied in 1% steps over a relatively large range. Further, by observing the number of teeth on gear 260 (this information can readily be stamped on one side face of each gear), subtracting the number of teeth from 100 and applying a constant, an operator can in a moment readily determine the percentage difference in the rate of advance of either section of yarn advancing means 76 and the surface speed of either section of heater roll 110. The same is true with respect to the rate of operation of yarn advancing means 188 relative, to that of heater roll gear 258 is the determining factor.

a ita e Secured to the outside end face of pinion232 byxmeans of screws 296 and'298 is a disc cam. 300,:1and secured to the face of the disc cam by means of a screw- 302 is a small bushing 304 andthimble305 aboutnwhich. is looped one end of a-fiexible cable 306. Flexihlec-able 306 extends through anopening 308 in housing 52 and about a guide pulley 310 tothe disengaging means which acts to stop operation of the twister array 42 andinsures that clutch 223 becomes disengaged by rotation. of stub shaft 230 when operation of: the spindlearray 42 is terminated. A. dog 312 .ispivotal'ly secured to support housing 52 by means of a screw314 and, in normal operation, engages a cam surface 316 on cam .3010 to prevent rotation of the cam. and disengagement of clutch 223. The upper end of dog 3-12 is connected through a'link 318 to the core 320 of a solenoid .322, and by electrically connecting solenoid 322 to a conventional electrical stop motion means,- not illustrated, and spring biasing cable 306, automatic stopping of; both the edge crimping component of the apparatus and the take-up component of the apparatus can be simultaneously efiected upon yarn breakage. With this arrangement, control rod 238 is employed only to place the apparatus in operation. If automatic stopping is not desired, disc cam v300 is rotated with respect to pinion .232 such that when the apparatus is in operatiomcable 306 extends through the axis of rotation-of cam 300-, solenoid322 is disconnected, and dog 312 is manually moved from- .operative position.. Both stopping and starting of the apparatus is then effected by means of control rod 238. i

The reference numeral 326 indicates a support arm which constitutes a part of the blade holder means 162.

This arm. has a top portion 327 which, in normal opera.- tion, extends in a generallyhorizontal plane, an arcuate shank portion 328, and a centrally bored boss portion 329, and is pivotally secured to housing 52 by means of a pin 330' extending through the here of boss portion 329. The top portion 327 of arm 3.26 is provided with a gibbed way and slidably mounted in this way is a flattened member 332 adjustably-positioned with respect to .support arm 326 by means of an adjusting screw 334 which extends through a dependingfportion 336, of arm memher 332 and is threaded into the upper extremity of support arm 326. Adjusting screw 334 is provided with a peripheral groove which engages the inside edges of a notch 338 in the depending portion of arm member 332 to insure that the arm member moves longitudinally with adjusting screw 334 and remains in any selected position.

' The right-hand end of arm member 332, as viewed in Figure 3 of the drawings, depends slightly and is tapered to form a wedge portion 339 having an upper face which extends generally tangentially to the peripheral surface of heater roll member 130, and a bottom face which extends generally tangentially to the peripheral surface of unheated roll 164. A bifurcated spring clamp 340 having a pair of legs 341 and 342 (see Figure 9) is secured to the upper face of arm member 332 adjacent the wedge shaped portion thereof, and the legs 341 and 342 have portions 343 and 344 which extendv through op- A posed notches in the sides of the arm member 332 generally perpendicularly to the longitudinal axis of the arm member. The terminal portions of legs 341 and 342 extend generally parallel to the bottom face ofwedge shaped portion 339 and are biased against the surface thereof by the resiliency o fthe spring clamp. This makes it possible for one to insert a blade member between the terminal portions of the legs 341 and 342 and the bottom face of wedge shaped portion 339 and to abut the back edge of the blade member against the portions 343 and 344 which extend generally perpendicularly to the longitudinal axis of arm member 332 so that-the blade member is thereby: precisely positioned with respect to the arm member. This simple blade holding means. ,is also, ed eat s sa is; t e reas n that the a m i6 inember 332canreadily be made-of copper or-othei' metal haying a relatively high; thermal conductivity so that heat is rapidly 'conducted frorn the blade member.

A further advantage of the blade. Yholding means is that wedge shaped plortion339 extends between the blade member and theheater roll and serves to partially insulate, thehlade member from the heater roll. Still anotheradvantage of the blade holding means is that it .is so constructed that the yarn can be passed in light slid ing contact withthe -bottom face of the blade and rapidly cooled following its passages about the blade edge.

Pivotally attached to the lower portion of support arm 326 by means of a pin 3-46 is a rod detent member 348 having an arcuate portion 350 and a straight portion 352 with a threaded end 354. The straight portion of rod detent member 348 extends through a bore in a cylindrical stu guide 356v which is pivotally secured to the side housingSZ; A- spiral compression spring 358 is mounted on the straight portion of detent rod 348 and is maintained in a compressed condition by means of nut 360 so that it bears against one side of guide stud 356 and thus. normally urges arm 326 to pivot in a clockwise direetion as viewed in Figure 3 of the drawings. To ad l lfitably limit the maximum extent to which support arm 326 can bepivoted inwardly toward unheated roll 1564.1 supp r rm 3 s provi ed with an integra formed tap 364 bored to receive a set screw 366 which bears against housing 52 when support arm 326 is in operative position. .It will be seen that by adjustment of set screw 366 and by adjusting screw 334, both the a e t at t e bl de 160 m e w a tangent t th periphery of heater roll 111} and the degree to which arm member 332 extends between rolls and 164 can readily be adjusted to provide an optimum angle in the yarn path as an end of yarn passes from heater roll 110 about the edge of the blade and thereafter about unheated roll 164. The curved portion of detent rod 348 permits support arm 326 to be pivoted outwardly such that a straight line extending from the center of pin 346 tothe axis of rotation of stud 356 passes through the pivot axis of support arm 326 as the support arm. is pivoted outwardly from cold roll 164 so that the bias of spring 358 thereafter urges the support arm 326 to pivot in a counterclockwise direction as viewed in Figure 3. The maximum extent to which support arm 326 can be pivoted in this manner is limited by the contact of arcuate portion 350 of detent rod 348 with the boss portion 329of cylindrical support arm 326, so that when the support arm is pivoted to a maximum extent in a counterclockwise direction as viewed in Figure 3, it is held in this position by the bias of spring 358 andthe unsupported end of arm member 332 is in a convenient position for changing the blade member 160. To assist in pivoting the. support arm 326 from operative position to blade changing position and vice versa, there is provided a handle 368 which can suitably be formed iiitegrally with arm 326.

In operation, the apparatus is equipped with gears and capstans for the yarn advancing means such that annular member of yarn heater 108 has a surface speed approximately equal to or slightly in excess of that of portion 84 of roll 74 and preferably from about 1% to 15% in excess of the surface speed of surface 84 of roll 74, cold roll 164 has a surface speed slightly less than the surface speed of annular member 130 and preferably from, 5% to 25% less than the surface speed of annular member 130, portion 88 of roll 74 has a surface speed less than the surface speed of portion 84 of roll 74 and preferably from 5% to 15% less, roll has a surface speed of from 5% to 40% and preferably from 15% to 35% less than the surface speed of portion 88 of roll 74, and such that annular member 132 of heater 108 and roll 190 have approximately equal surface speeds (i.e. preferably not more than 5% to 15% difference); in

other words, the apparatus is preferably set p so that type of yarn to be processed. An electrical current is then supplied to heater 108 such that annular members 130 and 132 are heated to a temperature of at least about 180 F. and preferably a temperature of at least about 260 F., but not to such a high temperature as to result in the yarn being heated above its sticking temperature. With the clutch 223 disengaged and take-up means 42 inoperative, one or a plurality of yarns are then threaded from supply means 12 and 14 through, in each instance, one of the tension regulators 28 and 30 to guide means 62. 'Each ofthe yarn ends is then posisitioned in separate grooves of guide means 62 and is thereafter passed through the comb guide 66 to roll 74 of yarn advancing means 76. The yarn ends are then wrapped counterclockwise (as viewed in Figure 3) one or more turns about the larger diameter portions of rolls 74 and 82 and are thereafter passed through the comb guide 102 such that the teeth of the guide maintain the the yarns in spaced relationship to each other.

Each of the yarns is then placed in one of the grooves in the cylindrical member 130 of yarn heater 108 and, with support arm 326 pivoted outwardly from housing 52 so that the blade member 160 is in inoperative position,

the yarn ends are drawn in a partial wrap about unheated roll 164 and to spiral yarn guide 178. Support arm 326 is then pivoted such that blade member 160 is disposed between rolls 164 and 110 and, such that the yarn ends pass about the blade member in an acutely angular path with the edge of the blade at the apex of the angle. The yarn ends are then threaded through spiral guide 178 such that they are retained in spaced relationship to each other and are passed one or more turns about the smaller diameter portions of rolls 74 .and 82. The yarn ends are then threaded through comb guide 184 such that they are maintained in spaced apart relationship and each of the yarn ends is placed in a different one of the grooves in annular member 132 of yarn heater 108 and are led in a partial wrap around the yarn heater, about guide pin 186 and to yarn advancing means 188. The yarn endsare then wrapped one or more turns about rolls 190 and 208, passed into contact with oil roll 34 through a partial wrap, and are then drawn through guide means 40 to the twister array 42. The apparatus is then placed in operation by means of control rod 238 and runs without further attention until a yarn supply becomes depleted or a take-up package becomes filled to capacity except that if a yarn end breaks, operation of the apparatus is automatically terminated by solenoid 322 in the manner previously described.

In the above description of one specific embodiment of the apparatus and the method for using the same it has been assumed that the apparatus is to be employed for performing a combination of edge elasticizing and thermal post-treatment operations, but as previously mentioned, the apparatus can be employed to perform either of these operations individually. To perform an edge elasticizing operation without a thermal post-treatment operation on one or a plurality of yarns, the apparatus is threaded as previously described except that after passing about cold roll 164, the yarns are about guide pin 186 and are thereafter passed to yarn advancing means 188 without being advanced a second time by the yarn advancing means 76. Gears are then selected such that the relative rate of operation of yarn advancing means 76 and yarn advancing means 188 is such as to provide a proper degree of-overfeed for edge elasticizing the particular yarn being processed.

To perform a thermaLpost-treatment operation on one withdrawn from heater roll 110, passed about guide pin 186. with or without contact with cold roll 164 and is thereafter passed'directly to yarn advancing means 188 without being advanced a second time by yarn advanclng means 76. Contact with cold roll 164 is usually advantageous since it results in more rapid cooling of the yarn and enables one to maintain the yarn under a lower tension at the point where it departs heater roll 110. Gears are then selected to result in yarn advancing means 76 and188 being operated at a proper rate to give the desired degree of overfeed for a thermal post-treatment operation. Of course, in this procedure it is necessary that an elasticized yarn or yarns be furnished by the yarn supply means 12 and 14 since the yarn is not passed about the edge of the blade member and, in fact, the blade member 160 may be completely removed when the apparatus is employed for this purpose. In this respect it should also be mentioned that the degree of overfeed required for best results with torque elasticized yarns is generally much less than that required with edge elasticized and mechanically crimped yarns and whereas from 15% to 35% overfeed generally gives the best results with edge. elasticized and mechanically crimped yarns, from 5% to 20% overfeed generally gives the best results in performing a thermal post-treatment operation upon torque elasticized yarns.

Apparatus according to this invention can also be employed to thermally shrink unelasticized thermoplastic yarns, for example, in the manufacture of welt yarns for ladies hosiery, and'represents a material advance over the apparatus presently employed for this purpose. Commercially available thermoplastic yarns generally have from about 5% to 25% residual shrinkage so that they will shrink by this amount when subjected to the elevated temperatures employed in boarding, scouring, and dyeing operations, and it is necessary that this residual shrinkage be eliminated before the yarns are employed in the knitting of the welt portion of ladies hosiery or for other similar purposes since, otherwise, subsequent shrinkage of the yarn will distort the stitch and shape of the finished fabric or knit article; At the present time, the most common procedure for removing the residual shrinkage from thermoplastic yarns comprises winding the yarn upon a collapsible core and thereafter heating the yarn in a steam chamber or the like.

This procedure has the disadvantage that it results in the yarn being held at an elevated temperature for a prolonged period with consequent yellowing and loss in tensile strength. It is a further disadvantage of such a procedure that the yarn through the yarn package is not evenly contracted so that when the yarn is thereafter formed into'fabrics, the resulting fabrics do not have a uniform appearance. It has also been suggested that thermoplastic yarns be beat contracted by passing them into contact with a stationary heater, but this procedure has not met with any appreciable degree of commercial success for the reason that if the yarn is placed under sufiicient tension to attain a satisfactory degree of contact with the yarn heater, the tension in the yarn is so high that good thermal shrinkage is not attained, and if one places the yarn under a sufiiciently low tension to obtain good thermal contraction, a satisfactory degree of contact with the yarn heater is not obtained. The last mentioned procedure has the further disadvantage that the yarn is unnecessarily abraded as a result of its rubbing contact with the yarn heater.

Apparatus according to the present invention makes possible a procedure for thermally contracting thermoplastic yarns with none of the above disadvantages. With the apparatus of this invention the yarn engaging surface ofthe yarn heater moves with the yarn so that there is no'abrasion of the yarn and a high tension to drag All n vet the heater surface isiiot re" y he iiit du'ced t the ineving heated surface under su-flicient tension to obtain an excellent degree of nbsen ng of the yarn and intimate contact of all of feeding the yarn tothe heater at a selected linear rate and withdrawingthe yarn from the heater at a selected constant linear'rate inherently results in the yarn being uniformly contracted so that fabrics formed therefrom have a uniform appearance. V

employ the apparatus as above described for thermally contracting thermoplastic yarns, the apparatus is threaded as described for performing a thermal posttt eatment on anelastici'zed yarn. Gears are then selected to result in the yarn beingadvanced by yarn advancing means 76 at a rate 'sufliciently in excess of'the rate at whichthe yarn is advanced by means 188 to provide the desired. degree of thermal shrinkage, and since it is generally desirable to remove as much of the residual shrinkage in'the yarn as possible, the rate of overfeed byadvancingmeans 7 6 with respect to meahs188 should generally be the maximum possible without thje yarn going slack or, in other words, from to 40% depending upon the residual shrinkage in the particular yarn being processed. .In thisprocess, the surface speed of the yarn heater can be varied from a rate p roxi ately equal to that at which the yarn is advanced by means 76 to the rate at which the yarn is advanced by means 188, but

to obtain v better contact between the yarn and the heater surface, it is generally preferable for the surface speed of the heaterto be approximately equal to or slightly in excess (i.e. from 1% to 5% greater) than the rate at which the yarn is advanced byrneans 76. V w r Inview of the above discussion it will also beseenthat apparatus according to this invention can suitably be employed for performing a combined hot stretching and thermal contraction operation uppn a thermoplastic yarn. Such a combined operation is presently performed upon thermoplastic yarns in the manufacture of tire cord and the like, and particularly in the case ef polyethylene terephthalate yarns and nylon 66 yarns resultsirr a product having a higher tensile strength, a higher modulus of elasticity, and a product which is more stable than can be produced by means of a thermal contraction operation alone. Apparatus is presently available for satisfactorily performing a combined hot-stretching and thermal contraction operation in the manufacture of tire cord from thermoplastic yarns, but the apparatus of this invention nevertheless represents a material advance for the reasons that it is simpler and more versatile than the apparatus presently available. In addition, it results in a more satisfactory product for the reason that the thermal contraction step of the combined operation can be more efficiently performed.

To perform a combined hot stretching and thermal contraction operation with apparatus as above described, the apparatus is threaded as for performing a thermal post-treatment operation on an elasticized yarn, and gears are then selected which result in the yarn heater having a surface speed in excess of that at which the yarn is advanced by means 76 and by means 188. The fact that the yarn heaters surface speed is in excess of the rate atwhich the yarn is advanced by means 76 re-:

, yar 'oiitaets' the heater ihe de'gree ef'eontact is s5 sugar that the yarn can readily slide over the surface or the heater, and since the yarn has a lower tensile strength when heated, stretching of the yarn is confined to az one extending from a point in the yarn path immediately prior to that at which the yarn contacts the heater to a point in the yarn path where the degree of contactbetween the yarn and the heater surface is sufficient to prevent the yarn from sliding upon the heater surface. The yarn can be hot stretched at this point in the yarnpath any desired amount short of that at which the yarn loses uniformity, but the optimum degree of hot stretching is generally from 1% to 15% depending upon the ticular yarn being processed. The amount that the'yarn is thereafter thermally contracted as it leavesthe heater surface depends upon the rate of movement of the heater surface relative to the rate of movement of the yarn engaging surfaces' of advancing means 188 and, in most instances, it is advantageous to select gears for the apparatus such that the yarn is contracted the maximum amount possible or, in other words, from 5% to 25% depending upon the particular yarn being processed.

Apparatus according to this invention is also suitable for performing a combination hot stretch and edge elastici'zing operation according to the method of US. application S. N. 630,325. In this type of'combined operation the apparatus is threaded and operated as above described for performing an edge elasticizing operation alone except that in this instance heater roll 108 geared relative to yarn advancing means 76 and '188 su ch that the yarn is hot stretched as it passes frb'm advancing means 76 to the heater roll. I

There are also various other procedures for threading up apparatus as above described to perform various coin binations of operations such as cold drawing, hot stretching, thermal contracting, heat-setting, edge elasticizing, thermal post-treating, oiling, and plying. For example,

one or several yarns can be passed from guide 62 to advancing means 188 and cold drawn as they are passed about pin 186 to the first section of advancing means 76 and thereafter thermally contracted as they are passed about heater roll 108 to the second section of advancing means 76; or one or several yarns can be passed from guide 66 to the first section of yarn advancing means 76, hot stretched as they are then passed through guide means 102 to the first sectoin of heater roll 188, passed again through guide 102 and back to the first section of heater roll 108 so that they are in contact with this section of the heater roll through more than 360, thermally contracted as they are passed to the second section of advancing means 76 and heatsset as they are passed about the second section of heater roll 108 to yarn advancing means 188. If it is not desired that the yarn or yarns be oiled, they can be passed directly from the advancing means 188 through appropriate guide means to the take-up means 42 so that they do not contact the oil roll and, when a plurality of yarnends are being processed they can be collected individually without being plied together by the provision of separate take-up means for each end of yarn. v

In view of the above description, various other modifications in the apparatus of this invention and procedures for employing the same will be readily apparent to those skilled in the art.

Having thus described our invention and-one specific embodiment thereof, what We desire to claim and secure by Letters Patent is:

1. Apparatus for processing. a running length of yarn comprising-in combination, a yarn supply means, a yarn heater means, a blade means having a sharp edge positioned adjacent said heater means, guide means to guide an end of yarn into contact with said heater meansand thereafter about ,said blade means in an acutely angular path withssaid edge positioned at the apex of. theanglfi,

yarn advancing means to withdraw the yarn from said blade means and advance the same at a selected linear rate, guide means to again guide said yarn into contact with said heater means, and a second yarn advancing means to thereafter withdrawsaid yarn from said yarn heater means at a selected linear rate less than said first mentioned linear rate.

2. Apparatus according to claim 1 wherein said heater means comprises a heated roll and including driving means forsaid roll.

3. Apparatus for processing a running length of yarn comprising, in combination, a yarn supply means, a yarn heater means comprising a stepped roll having two heated cylindrical surfaces of different diameters and means for driving said roll, a blade means having a sharp edge positioned adjacent said heater means, guide means to guide an end of yarn into contact with the heated cylindrical surface of larger diameter of said heater means and thereafter about said blade means in an acutely angular path with said edge positioned at the apex of the angle, yarn advancing means to withdraw the yarn from said blade means and advance the same at a selected linear rate, guide means to guide said yarn from said yarn advancing means into contact with the heated cylindrical surface of smaller diameter of said heater means, and a second yarn advancing means to thereafter withdraw said yarn from said heated cylindrical surface of smaller di- 'ameter at a selected linear rate less than said first mentioned linear rate.

4. Apparatus according to claim 3 wherein said stepped roll and said second yarn advancing means are operatively driven such that the surface speed of said smaller diameter cylindrical surface is approximately equal to the linear'rate at which the yarn is advanced by said second yarn advancing means.

5. Yarn processing apparatus comprising in combination'a yarn supply means, a first yarn advancing means comprising a first member to advance the yarn along a linear path at a first selected linear rate, a yarn heater roll having first and second cylindrical surfaces of different diameters, means to heat at least a peripheral portion of each of said cylindrical surfaces, guide means to guide said yarn from said first yarn advancing means into contact withv a heated portion of the cylindrical surface 'of said heater roll of larger diameter, a blade means hav- 'ing a sharp edge positioned proximate said cylindrical surface of larger diameter, an unheated roll to guide the .yarn from said yarn heater roll about said blade edge in an acutely angular path with said edge positioned at the apex of the angle, said first yarn advancing means comprising a second member to advance said yarn from said unheated roll along the yarn path at a second selected linear rate, means to guide said yarn from said second member of said first yarn advancing means into surface contact with the cylindrical surface of said heater roll -having the smaller diameter, a second yarn advancing means to thereafter withdraw the yarn from said cylindrical surface of smaller diameter and to advance the same at a third selected linear rate which is less than said second linear rate, and means to thereafter collect said yarn.

6. Apparatus according to claim 5 including driving means for each of said, yarn advancing means and said yarn heater roll to operatively provide rotation of said heater roll at a relative rate such that said cylindrical surface of larger diameter has a surface speed in excess of,

the' linear rate at which the yarn is operatively advanced by said first member of said first yarn advancing means and such that said cylindrical surface of smaller diameter has a surface speed approximately equal to the linear rate at which said yarn is operatively advanced by said second.

yarn advancing means.

7. Apparatus according to claim 6 wherein each of said yarn advancing means and said heater roll are operatively driven such that said cylindrical surface of larger diameter has a surface speedof from 1% to 15% greater 16 than the linear rate at which the yarn is advanced by said first member of said first yarn advancing means and the surface speed of said cylindrical surface of smaller diameter differs not more than 15% from the linear rate at which the yarn is advanced by said second yarn advancing means.

8. Apparatus according to claim 7 wherein said second member of said first yarn advancing means operatively advances the yarn at a rate which is from 5% to 15 less than the rate at which the yarn is advanced by said first member of said first yarn advancing means.

9. Apparatus according to claim 8 wherein said second yarn advancing means operatively advances the yarn at a ,means to guide said yarn into contact with the peripheral surface of said oil roll through an arc of less than 360, drive means to positively rotate said oil roll and means for supplying a coating of oil to the peripheral surface of said oil roll where said yarn is in contact therewith.

12. Apparatus for processing a plurality of ends of yarn comprising, in combination, a plurality of yarn supply means, a plurality of yarn tension regulators to receive, in each instance, an end of yarn from one of said supply means, a yarn heater roll having a pair of grooved cylindrical surfaces of different diameters, means to heat said cylindrical surfaces, means to guide said ends of yarn from said tension regulators into, in each instance, a different one of the grooves in the cylindrical surface of larger diameter, a blade member with a sharp edge positioned proximate said cylindrical surface of larger diameter, a yarn advancing means including at least one driven roll member, means to guide said yarn ends, in spaced relationship to each other, from said cylindrical surface said yarn advancing means and thereafterv to the cylindrical surface of smaller diameter of said yarn heater, a second yarn advancing means to receive said yarn ends following their contact with said cylindrical surface of smaller diameter and to positively advance the same at a linear rate less than that at which they are advanced by said first yarn advancing means, and means to thereafter twist together said plurality of yarn ends and collect the resulting plied strand.'

. 13. In an apparatus for elasticizing a thermoplastic yarn and including a roll heater having a cylindrical heated surface, a blade means with a sharp edge positioned adjacent said heated surface, means to guide said yarn into contact with said heated surface, and yarn advancing means to withdraw said yarn from said heater about said edge in an acutely angular path with said edge positioned at the apex of the angle; the improvement which comprises a second cylindrical heated surface on said yarn heater, said second surface being of smaller diameter than said first mentioned heated cylindrical surface, means to guide said yarn from said yarn advancing means into contact with said second heated cylindrical surface, and a second yarn advancing means to thereafter receive the yarn and positively advance the same at 17 each of 'said' yarn" advancing means and said heater roll such that the rate at which said yarn is advan-ced'by said second yarn advancing means is less than the rate at which the yarn is advanced by said first yarn advancing means, and said heater roll has a peripheral surface speed approximately equal to the rate at which the yarn is advanced by said second yarn advancing means.

15. Apparatus for post-treating an end of elasticized yarn comprising a first yarn advancing means, asecond yarn advancing means, a heater roll disposed in intermediate yarn flow relationship with respect to said two yarn advancing means, driving means to operatively drive' each of said yarn advancing means and said heater roll" such that the rate at which'the yarn is advanced by said second yarn advancing means is less than the rate at which the yarn is advanced by said first yarn advancing means, and said heater roll has a peripheral surface speed approximately equal to the rate at which the yarn is advanced by said second yarn advancing means, said driving means comprising a multiple gear composed of a first gear component for driving said heater roll, a readily exchangeable gear component for driving said first yarn advancing means and asecond readily exchangeable gear component for'driving said second yarn advancing means, and a pair of smaller gears connecting, in each instance, said first and second yarn advancing means with said multiple gear,cand'meansto'precisely adjust the distance of each of said smaller gearsfrom the axis of rotation of said multiple gear.

16. Apparatus for post-treating an end of elasticized yarn comprising a first yarn advancing means, a second yarn advancing means, a heater roll dispose-d in intermediate yarn flow relationshipwith respect to said two yarn advancing means; driving means to operatively drive each of said yarn advancing means and said heater roll such that the rate at which said yarn is advanced by said second yarn advancing means is less than the rate at which the yarn is advanced by said first yarn advancing means, and said heater roll has a peripheral surface speed approximately equal to the rate at which the yarn is advanced by said second yarn advancing means, said driving means comprising a multiple gear composed of a first gear component for driving said heater roll, a readily exchangeable gear component for driving said first yarn advancing means and a second readily exchangeable gear component for driving said second yarn advancing means, said multiple gear carrying a clutch element on one side face thereof, and including a gear coaxially disposed with respect to said multiple gear and carrying a second clutch element, and means to effect axial displacement of said multiple gear to result in engagement and disengagement of said two clutch elements.

17. Apparatus for processing a running length of yarn comprising a support housing, a stub shaft carried by said support housing, a multiple gear journaled for rotation about said stub shaft, said multiple gear comprising a plurality of gear elements, at least one of which is readily exchangeable for gear elements of different sizes, a yarn heater roll carried by said support housing, means to drive said yarn heater roll from one gear element of said multiple gear, at least one yarn advancing means carried by said support housing, a small gear meshing with said readily exchangeable gear element for driving said yarn advancing means, adjusting means for varying the distance between the axis of rotation of said small gear and the axis of rotation of said multiple gear, whereby the relative rate of operation of said yarn advancing means and said heater roll can readily bevaried and the relative rates of operation are directly dependent upon the relative sizes of the gear elements of said multiple gear.

18. Yarn processing apparatus comprising, in combination, a support housing, a drive shaft journaled through said support housing, a drive gear carried by said drive shaft, a sleeve carried by said support housing and extending parallel to said drive shaft, a driven gear jour naled about said sleeve and meshing with said drive gear, said driven gear carrying on one side face thereof a disc type clutch member, a stub shaft extending through said sleeve in threadwise engagement therewith, a multiple gear journaled about said stub shaft, said multiple gear carrying a second disc type clutch member on one face thereof to mate with the clutch member on said driven gear, a plurality of yarn advancing means carried by said support housing, a heater roll carried by said support housing, a plurality of small gears for driving said heater roll and each of said yarn advancing means from said multiple gear, a pinion secured to said stub shaft, a slidably mounted control rod carried by said support housing, said control rod having a gear rack on one end thereof meshing with' said pinion so that lengthwise movement of said control rod results in axial displacement of said multiple gear to thereby effect engagement or disengagement of said two clutch members and starting or stopping of the operation of each of said yarn advancing means and said heater roll.

19. In a yarn processing apparatus the combination comprising a drive shaft, a driving gear carried by said shaft, a fixed sleeve extending generally parallel to the axis of rotation of said driving gear, a driven gear journaled about" said sleeve, a stub shaft threaded through said sleeve, control means for rotating said stub'shaft to result in axial movement thereof, a clutch member carried by said driven gear, a multiple gear journaled for for starting and stopping said take-up means, and means connecting said stub shaft with said disengaging means, whereby manipulation of said control means serves to simultaneously start and stop each of said yarn advancing means, said heater roll and said take-up means.

20. Apparatus for elasticizing a running length of yarn comprising, in combination, a heater roll, a blade member with a sharp edge operatively positioned proximate the surface of said heater roll, and means for securing said blade member in operative position, said last named means including an elongated arm member having a fiattened and tapered end portion operatively extending between said blade member and said heater roll, said tapered end portion of said arm member being of sufficient size to shield substantially said entire blade member, with the exception of said sharp edge, from said heater roll, a bifurcated spring member secured to said arm member with intermediate portions of the legs of said spring member extending generally perpendicularly to the longitudinal axis of said arm member in contact with the edge of said blade member remote from said.

said terminal portions of said legs forcefully urge said blade member into contact with said tapered end portion, whereby said blade member is pressed firmly against said arm member, is precisely positioned by abutment against said intermediate portions of said legs and is thermally insulated from said heater roll by said tapered end portion of said arm member.

21. Yarn processing apparatus comprising in combinationa support housing, a shaft journaled through said support housing, a heater roll carried by said shaft, a

spawns blade member with a sharpened edge operatively positioned proximate to the peripheral surface of said heater roll, and holding means for said blade member comprising a first arm member pivoted to said housing, a second arm member carried by said first arm member and extending at generally right angles thereto, said second arm member having an unsupported end operatively positioned proximate said heater roll, clamp means carried by said unsupported end for securing said blade member, means for adjusting the position of said second arm member longitudinally with respect to said first arm member, biasing means urging said first arm member into operative position, and adjustable stop means to limit the extent to which said first arm member can be pivoted by said biasing means, so that by movement of said second arm member relative to said firstarm member and adjustment of said stop means, both the plane of said blade member relative to a tangent to said heater roll and the distance of said edge from said heater roll can be precisely adjusted.

22. Apparatus according to claim 21 wherein said biasing means comprises a detent rod pivotally. attached at one end to said first arm member, a support stud extending from said housing and slidably engaging said detent rod, said support stud being pivotal about an axis generally perpendicular to the longitudinal axis of said detent rod, and a compression spring carried on the unsupported end of said detent rod and abutting against said support stud.

23. Apparatus according to claim 22 wherein the positional relationship of said support stud, the pivot axis of said first arm member, and the point at which said detent rod is pivotally attached to said first arm member is such that as said blade holding means is pivoted from operative position, a line extending from said point of attachment to said support stud passes through the pivot axis of said first arm member whereby said biasing means thereafter urges said first arm member to an inoperative position.

24. Apparatus for processing a running length of thermoplastic yarn comprising means, including a yarn heater, to impart an elastic nature to said yarn, advancing means to positively advance said yarn at a selected linear rate following its passage into operative relationship with said heater, means to guide said yarn'from said advancing means into operative relationship with said heater a second time, a second yarn advancing means to thereafter engage said yarn and positively advance the same at a linear rate less than said first mentioned rate, and means to thereafter collect said yarn.

References Cited in the file of this patent UNITED STATES PATENTS 798,276 Fredenburgh Aug. 29, 1905 2,244,415 Arnold June 3, 1941 2,325,060 Ingersoll July 27, 1943 2,455,173 Hitt NOV. 30, 1948 2,509,741 Miles May 30, 1950 2,584,779 Averns Feb. 5, 1952 2,639,485 Ambler May 26, 1953 2,736,944 Herbert et al Mar. 6, 1956 2,803,105 Stoddard et a1 Aug. 20, 1957 2,864,229 Seem et a1. Dec. 16, 1958 FOREIGN PATENTS 210,620 Australia Oct. 9, 1957 214,093 Australia Apr. 2, 1958 

